Syndesmotic Injury
Other Names
- High ankle sprain
- Syndesmotic Tear
- Tibioperoneal diastasis
Background
- This page refers to injuries of the distal Tibiofibular Syndesmosis
History
- The first case of syndesmotic injury was described by Quenu in 1907[1]
Epidemiology
- Far less common than lateral ankle sprains
- Time lost: ranges from 0 to 137 days; averages ranging from 10 to 14 days up to 52 days[4]
Introduction




General
- Classically called a high ankle sprain, represents injury to the distal tibiofibular syndesmosis
- The diagnosis is typically made clinically and supported by imaging
- Management largely depends on the stability of the joint and associated injuries
Pathophysiology
- Incomplete/ partial sprain
- Torn: partial or complete tear of anterior portion of the AITFL
- Intact: PITFL, IOM
- XR: Mortise intact
- Complete sprain/ disruption
- Torn: AITFL, PITFL, IOM
- XR: Widened mortise
Mechanism
- External rotation, hyperdorsiflexion and talar eversion (most common)
- Hyperdorsiflexion with external rotation
- Axial loading
- Inversion
Associated Conditions
Anatomy of the Distal Tibiofibular Syndesmosis
- Series of ligaments that connect the distal Fibula and Tibia
- Stabilizing ligaments
- Anterior Inferior Tibiofibular Ligament (AITFL)
- Superficial and deep components of the Posterior Inferior Tibiofibular Ligament (PITFL)
- Interosseous Membrane of the Leg (IOM) of the leg, sometimes called Interosseous Ligament (IOL)
- Inferior transverse ligament
Risk Factors
Sports
- Football[2]
- Ice Hockey
- Soccer
- Alpine Skiing[7]
Differential Diagnosis
Differential Diagnosis Leg Pain
- Fractures & Dislocations
- Muscle and Tendon Injuries
- Neurological
- Vascular
- Other
- Pediatric Considerations
- Tibial Tubercle Avulsion Fracture
- Tibial Tuberosity Apophysitis
- Toddlers Fracture (Tibial Shaft Fracture)
Differential Diagnosis Ankle Pain
- Fractures & Dislocations
- Muscle and Tendon Injuries
- Ligament Injuries
- Bursopathies
- Nerve Injuries
- Arthropathies
- Pediatrics
- Fifth Metatarsal Apophysitis (Iselin's Disease)
- Calcaneal Apophysitis (Sever's Disease)
- Triplane Fracture
- Other
Clinical Features

History
- Patients should be able to describe mechanism of injury
- Swelling is often absent in isolated syndesmotic injuries (may be present if lateral or medial ankle sprain)
- Trouble bearing weight
Physical Exam: Physical Exam Ankle
- Pushoff during gait may be abnormal[9]
- Tenderness along syndesmosis, AITFL, PITFL
- Antalgic heel raise or calf raise
Special Tests
- Squeeze Test: apply pressure to medial and lateral calf
- External Rotation Stress Test: Apply external passive rotation force to ankle
- Cotton Test: attempt to translate talus from side-to-side with ankle in neutral
- Fibular Translation Test: stabilize tibia, translate fibula in anterior-posterior direction
- Crossed Leg Test: patient seated, crosses affected leg over unaffected leg
- Stabilization Test: tape patient's leg just above the ankle joint in an attempt to stabilize the syndesmosis
- Forced Dorsiflexion Test: Ankle placed into dorsiflexion, repeated while compressing tibia and fibula
Evaluation
-
Measuring the tibiofibular clear space[10]
-
Ankle XR with syndesmotic widening, widening of medial clear space[11]
-
Ankle XR showing widening of distal syndesmosis[12]
-
Ankle XR status post tightrope surgery[13]
Radiology

- Weight bearing mortise view
- Can be helpful to evaluate displacement, patients may not tolerate
- Consider bilateral weight bearing
- Tibiofibular clear space
- Definition: space between the medial border of the fibula, lateral border of the posterior tibial prominence
- Measure: 1 cm above tibial plafond
- Normal: Intact syndesmosis should be < 6 mm
- Tibiofibular overlap
- Definition: maximal overlap between the medial border of the fibula, the lateral border of the distal tibia
- Measure: 1 cm above tibial plafond
- Normal: tibiofibular overlap for the AP view is > 6 mm, mortise view > 1 mm
- Standard Radiographs Leg
- Strongly consider to evaluate for Maisonneuve Fracture
CT
- Can precisely assess the position of the fibula in the incisura
- More sensitive at 2-3 mm diastasis than radiographs[18]
- May identify avulsion fractures which occur in up to 50% of syndesmotic injuries[19]
MRI
- Benefits
- Good visualization of the AITFL and the PITFL
- Clearly define the lesion, associated injuries
- Useful in determining prognosis following a syndesmosis sprain
Ultrasound
- Not currently recommended for syndesmotic injuries
Classification

ESSKA AFAS Classification
- General
- Graded by acuity: acute (6 weeks or less), subacute (6 weeks to 6 months), chronic (greater than 6 months)[21]
- Acute
- Stable: lesion of AITFL, with or without IOL, intact deltoid
- Unstable: also includes deltoid ligament lesion
- Latent: diastasis compromises AITFL, with or without IOL, deltoid ligament lesion
- Frank: diastasis of all syndesmotic ligaments, deltoid ligament
- Subacute
- Reparable: adequate remnants of AITFL
- Non-repairable: inadequate remnants of AITFL
- Chronic
- Arthritic changes
- No arthritic changes
Grading of Syndesmotic Injury by MRI Findings
- Grade I
- MRI: Edema adjacent to an intact ligament
- Lesion: Stretching of the ligament without fiber disruption
- Grade II
- MRI: Thickening of the ligament with partial fiber disruption and associated edema
- Lesion: Partial tearing of the ligament
- Grade III
- MRI: Discontinuity of the ligament and extensive edema
- Lesion: Complete tear of the ligament
Management
Nonoperative
- Indications
- Simple syndesmotic sprains without diastasis or associated fracture
- Immobilization
- Short Leg Cast for 2 - 6 weeks with non weight bearing status
- There is no consensus on duration of immobilization[22]
- Proposed nonoperative strategy by Mulligan et al[23]
- Grade I sprains without diastasis
- Immobilization: 0-3 days
- Weight bearing as tolerated
- Grade II sprains with latent diastasis
- Immobilization: 3-7 days
- Weight bearing can begin after 1-2 weeks
- Grade III sprains with frank diastasis,
- Immobilization: Greater than 7 days
- Non weight bearing minimum of 2-3 weeks
- Grade I sprains without diastasis
Procedures
- Distal Tibiofibular Joint Injection
- No clear guidelines
- Consider corticosteroids, orthobiologics
- Corticosteroid Injection
- Sped up return to play in NFL players by approximately 10 days[24]
Operative
- Indications
- Non-fracture syndesmotic injury with displaced and widened mortise
- Syndesmotic injury with associated ankle fracture
- Goal[25]
- Restore ankle stability
- Maintain correct alignment of tibia and fibula to allow sufficient healing of the syndesmotic ligaments
- Technique
- Screw fixation
- Suturing of the syndesmosis
- Syndesmosis hooks
- Bioabsorbable screws
- Endo Buttons
- TightRope device
Rehab and Return to Play
Rehabilitation
- 3 phase program for syndesmotic sprain[26]
- Phase 1: joint protection, reduction of inflammation, and pain-free walking.
- Phase 2: Minimal pain, edema, and antalgic gait are present
- Goals: return of strength, mobility, and a normal gait
- Phase 3: jog, and hop repetitively without difficulty
Return to Play/ Work
- Needs to be updated
Complications and Prognosis
Prognosis
- General
- Greater recovery time is needed for syndesmotic injuries compared to lateral ankle sprain[27]
- Nonoperative treatment of stable, isolated syndesmotic injury
- Surgical fixation of isolated syndesmotic injury
- Taylor et al in a series of 6 patients found average RTP was 40.7 days, all patients reported good to excellent outcomes[30]
- Predictors of poor outcomes
- Predictors of good outcomes
- Egol et al found that greater age, male sex, absence of diabetes, lower American Society of Anesthesiologists (ASA) class all predicted better functional outcomes at a one-year follow-up[34]
Complications
- Overall complications
- Rate up to 68% in non-surgical management of isolated syndesmotic injuries[35]
- Heterotropic Ossification (HO)
- May not be radiographically evident until 6 months after the injury
- Taylor found 11 of 22 patients had radiographic HO at follow up without any difference in symptoms[28]
- Implant failure and screw removal
- Between 7% and 91% of screws loosen or break[6]
- Stiffness
- Pain with activity
- Residual painful instability
See Also
Internal
External
- Sports Medicine Review Ankle Pain: https://www.sportsmedreview.com/by-joint/ankle/
References
- ↑ Quenu E. Du diastasis de l’articulation tibio-peronie’re inferieure. Rev Chir (Paris) 1907;36:62-90. (In French)
- ↑ 2.0 2.1 Boytim MJ, Fischer DA, Neumann L. Syndesmotic ankle sprains. Am J Sports Med 1991;19:294-298.
- ↑ Wright RW, Barile RJ, Surprenant DA, Matava MJ. Ankle syndesmosis sprains in national hockey league players. Am J Sports Med 2004;32:1941-1945.
- ↑ Jones MH, Amendola A. Syndesmosis sprains of the ankle: a systematic review. Clin Orthop Relat Res. 2007;455:173–5
- ↑ 5.0 5.1 Norkus, Susan A., and R. T. Floyd. "The anatomy and mechanisms of syndesmotic ankle sprains." Journal of athletic training 36.1 (2001): 68.
- ↑ 6.0 6.1 Jones, Clifford B., Alex Gilde, and Debra L. Sietsema. "Treatment of syndesmotic injuries of the ankle: a critical analysis review." JBJS reviews 3.10 (2015).
- ↑ Fritschy D. An unusual ankle injury in top skiers. Am J Sports Med. 1989;17:282–5. 5–6. discussion.
- ↑ Ivins D. Acute ankle sprain: an update. Am Fam Physician. 2006;74(10):1717
- ↑ Spaulding S. Monitoring recovery following syndesmosis spraa case report. Foot & ankle international / American Orthopaedic Foot and Ankle Society [and] Swiss Foot and Ankle Society. 1995 Oct;:655–60.
- ↑ https://www.orthobullets.com
- ↑ Kellett, John J., et al. "Diagnostic imaging of ankle syndesmosis injuries: A general review." Journal of medical imaging and radiation oncology 62.2 (2018): 159-168.
- ↑ https://radiopaedia.org/cases/68182
- ↑ https://radiopaedia.org/cases/78719
- ↑ Takao M, Ochi M, Naito K, et al. Arthroscopic diagnosis of tibiofibular syndesmosis disruption. Arthroscopy 2001;17:836-843.
- ↑ Wright RW, Barile RJ, Surprenant DA, Matava MJ. Ankle syndesmosis sprains in national hockey league players. Am J Sports Med. 2004;32:1941–5.
- ↑ Nussbaum ED, Hosea TM, Sieler SD, Incremona BR, Kessler DE. Prospective evaluation of syndesmotic ankle sprains without diastasis. Am J Sports Med. 2001;29:3l–5
- ↑ Kellett, John J., et al. "Diagnostic imaging of ankle syndesmosis injuries: A general review." Journal of medical imaging and radiation oncology 62.2 (2018): 159-168.
- ↑ Ebraheim NA, Lu J, Yang H, Mekhail AO, Yeasting RA. Radiographic and CT evaluation of tibiofibular syndesmotic diastasis: a cadaver study. Foot & ankle international / American Orthopaedic Foot and Ankle Society [and] Swiss Foot and Ankle Society. 1997;18:693–8.
- ↑ Sclafani SJ. Ligamentous injury of the lower tibiofibular syndesmosis: radiographic evidence. Radiology. 1985;156:21–7.
- ↑ de-las-Heras Romero, Jorge, et al. "Management of syndesmotic injuries of the ankle." EFORT open reviews 2.9 (2017): 403-409.
- ↑ van Dijk CN, Longo UG, Loppini M, et al. Classification and diagnosis of acute isolated syndesmotic injuries: ESSKA-AFAS consensus and guidelines. Knee Surg Sports Traumatol Arthrosc 2016;24:1200-1216
- ↑ van Dijk CN, Longo UG, Loppini M, Florio P, Maltese L, Ciuffreda M, Denaro V. Conservative and surgical management of acute isolated syndesmotic injuries: ESSKA-AFAS consensus and guidelines. Knee Surg Sports Traumatol Arthrosc. 2016;24:1217–1227.
- ↑ Mulligan EP. Evaluation and management of ankle syndesmosis injuries. Phys Ther Sport. 2011 May;12(2):57-69. Epub 2011 Apr 2.
- ↑ Mansour AA, Porter DA, Young JP, Hammer D, Boublik M, Schlegel TF. Corticosteroid injections hasten return to play of National Football League players following stable ankle syndesmosis sprains. Orthop J Sports Med. 2013 Sep;14.
- ↑ Hunt KJ, Phisitkul P, Pirolo J, Amendola A. High Ankle Sprains and Syndesmotic Injuries in Athletes. J Am Acad Orthop Surg. 2015;23:661–673.
- ↑ Nussbaum ED, Hosea TM, Sieler SD, Incremona BR, Kessler DE. Prospective evaluation of syndesmotic ankle sprains without diastasis. Am J Sports Med. 2001 Jan-Feb;29(1): 31-5.
- ↑ Sman AD, Hiller CE, Rae K, Linklater J, Black DA, Refshauge KM. Prognosis of ankle syndesmosis injury. Med Sci Sports Exerc. 2014 Apr;46 (4):671-7.
- ↑ 28.0 28.1 Taylor DC, Englehardt DL, Bassett FH 3rd. Syndesmosis sprains of the ankle. The influence of heterotopic ossification. Am J Sports Med. 1992 Mar Apr;20(2):146-50.
- ↑ Nussbaum, Eric D., et al. "Prospective evaluation of syndesmotic ankle sprains without diastasis." The American journal of sports medicine 29.1 (2001): 31-35.
- ↑ Taylor DC, Tenuta JJ, Uhorchak JM, Arciero RA. Aggressive surgical treatment and early return to sports in athletes with grade III syndesmosis sprains. Am J Sports Med. 2007;35:1833–1838.
- ↑ Schepers, Tim, et al. "Technical aspects of the syndesmotic screw and their effect on functional outcome following acute distal tibiofibular syndesmosis injury." Injury 45.4 (2014): 775-779.
- ↑ Van Schie-Van der Weert, E. M., et al. "Determinants of outcome in operatively and non-operatively treated Weber-B ankle fractures." Archives of orthopaedic and trauma surgery 132.2 (2012): 257-263.
- ↑ Mendelsohn, Elliot S., et al. "The effect of obesity on early failure after operative syndesmosis injuries." Journal of orthopaedic trauma 27.4 (2013): 201-206.
- ↑ Egol, Kenneth A., et al. "Predictors of short-term functional outcome following ankle fracture surgery." JBJS 88.5 (2006): 974-979.
- ↑ Nussbaum ED, Hosea TM, Sieler SD, Incremona BR, Kessler DE. Prospective evaluation of syndesmotic ankle sprains without diastasis. Am J Sports Med. 2001;29:31–35
Created by:
John Kiel on 26 June 2019 19:53:55
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10 September 2025 14:59:06
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